Manufacture of roofing material



May 12, 1964 J. G. YOUNG MANUFACTURE OF ROOFING MATERIAL Filed June 23, 1958 w w H R z m n m R g m w m M m r n O v gxvm Q s a Ed D\ a a N. Jdfl w QM QM. Q\ N J a r m m a E. v w J 1 R2: 1| W E w 4 United States Patent 5,132,964 MANUFACTURE OF RQUFIN G MATERIAL James Glenn Young, Cincinnati, Ohio, assignor to The Philip Carey Manufacturing Company, Cincinnati, Ohio, a corporation of flhio Filed June 23, 1958, Ser. No. 743,738 1 (Ilaim. (Cl. 117-19) This invention relates to the manufacture of roofing material. By the term roofing material it is meant to include so-called roll roofing, strip shingles, and shingles, since all of these types of roofing may be manufactured by the same procedure except for the way in which the material is finally slit or cut.

Further, by the term roofing material is meant a material comprising a base which may be felted or Woven organic, glass or asbestos material coated with an asphaltic material and having on the upper side a layer of roofing granules. By upper side is meant that side which is exposed when the roofing material is laid on the roof.

In the manufacture of roofing material as outlined above, it is conventional to pass a web of the base material through a coating apparatus by means of which the asphaltic coating is applied to both sides of the web. From the coating apparatus, the web passes under one or more granule applying devices by means of which the granules are distributed on the traveling web. It is common practice today to apply to the web granules of different colors or shades from a series of granule applying mechanisms operated in timed sequence to apply to the web bands of granules of different colors.

It is also conventional to provide means for catching excess granules which spill off the web and to return these to a so-called spill hopper regardless of color, and the spill hopper may be arranged to apply a band of mixed color granules to the Web.

Conventionally also it is the practice to apply different granules to the butt portions and to the headlap. The headlap portion of a shingle or of a roll roofing or of strip shingles is that portion which is covered up-by the next higher strip of roll roofing or by the next higher shingle or strip shingle. Since this portion, the headlap, is not 7 exposed to view, a less expensive granule is generally applied and the headlap granules are generally all of the same color. The granules applied to the exposed portion are the expensive granules and it is in this portion that bands of different colors are generally applied.

After the granules have been applied to the Web, the granule side may contact a roll without sticking because the granules separate the roll from the asphaltic coating.

his the common practice, therefore, to pass theweb up- Wardly around the roll with the granule side of the web against the roll and then to apply an anti-stick material to the underside of the web (which is now uppermost) before the web passes in a reverse direction about another roll. The anti-stick material'may be sand, talc or mica or other material which will preventthe underside of the asphalt coated web from sticking to a roll or to an adjacent shingle or convolution in a package.

It results from the practice above outlined that far more granules are applied to the web than are required for corn- I plete coverage. With a No. 11 grading the amount of granules necessary to give complete coverage in substantially a single layer is about twenty-one pounds per one hun died square feet. A number 11 grading has reference to granule size and-is nearly, but not quite, an industry I standard. Each manufacturer of roofing granules sells a number 11 grading but the specific percentage of difierent particle sizes varies with the manufacturer. number 11 grading of one manufacturer in terms of percent granules retained on a Tyler screen is as follows.

A typical 3,132,964 Patented May 12, 1964 The specifications of other manufacturers differ slightly but not substantially from the above table.

Because of the Way in which the granules are currently applied, the actual weight of granules remaining on the completed roofing' material will run from twenty-eight pounds to forty pounds per one hundred square feet. The average weight will be in. the neighborhood of thirty-four pounds per one hundred square feet.

Years ago when granules were inexpensive and-usually dark in color, the waste in granules was considered inconsequential. However, in recent'years the demand has increased for light colored roofing material and granules in pastel colors and in white are very much more expensive than dark granules so that today the granule cost is an important factor in the total cost of the roofing material.

The excessive amount of granules remaining on the finished roofing material also detract from the appearance of the roofing material in that it has a lumpy, rough or blotchy appearance. Furthermore, in cases where there has been an excessive build up of granules and the web carrying the granules is passed around the first roll, there is a tendency for the web to crack or break.

With the foregoing considerations in mind, it is the principal object of the present invention to provide a method of manufacturing roofing material and applying granules thereto in such manner that substantially a single layer of granule is achieved.

- It is another object of the invention, by achieving a substantially single layer of granules to provide roofing material of greatly improved appearance. Roofing material according to the present invention will have arelatively smooth appearance because substantially all of the granules are firmly bonded in the asphalt layer, and substantially no granules are held mechanically, as by being discloses an exemplary embodiment.

Reference is made to the drawing forming a part hereof and in which:

FIGURE 1 is a somewhat diagrammatic view partially in elevation and partially in cross-section of an apparatus for coating the web and applying granules thereto.

FIGURE 2 is a fragmentary plan view of the web being treated; and I FIGURE 3 is a plan view of a typical strip shingle. A Web of roofing felt or asbestos or other suitable material is indicated at 10. The web passes. over the rollers 11,-12 and 13 and by means of the suitable controlled discharge spout 14 asphaltic material 15 is applied to the upper surface thereof. 'A roll 16 smooths out the layer of asphaltic material and is backed up by the roll 12. 17 indicates a tank to catch excess asphaltic material and the excess asphaltic material may drain through a pipe 18 to a reservoir 19. The excess asphaltic material in'the vessel 19 is returned through a pipe 20 by means of the pump P to the main source of supply for the spout 14.

The web having on its upper surface a coating of asphaltic material then passes under the granule applying section of the apparatus indicated generally at G. A series of hoppers have been indicated at 1, 2, 3 and 4 by means of which granules of four colors are applied. The hopper indicated at S is for spill granules. The hoppers 1, 2, 3 and dare cam operated as is well known, to lay down bands of different colors of granules as the web moves along. One of the spill hoppers is held in reserve for color changes and the other operates all the time so as to provide a uniform coating of spill over the entire band so that the colors appear to blend into each other more smoothly. 1

In FIGURE 2, showing by way of example a forty-eight inch web as might be produced on a forty-eight inch machine, the web 10 is shown in plan view and the Way in which the granules are applied may be clearly seen. In this figure, the web will ultimately be slit longitudinally along the lines aa, bb and cc, so that four strips result.

Each of these strips has a headlap portion and the headlap portions are indicated at it, while the exposed portions of the four strips are indicated at e. As pointed out above, the granules applied along the stripes h are inexpensive granules. These are applied by other hoppers in the area G (not shown). It, 2, 3, i and S are the ones which apply the bands in the areas or stripes e as indicated in FIGURE 2. It will be understood that the showing of hoppers is exemplary The hoppers indicated at.

' reduction in cost of materials but because of the increase only, and that more or less hoppers may be used. The

tour strips of roofing material, after slitting on the lines aa, bb and cc, maybe rolled up and used as roll roofing or they may be cut into strip shingles, as indicated in FIGURE 3, or they may be cut into individual shingles.

In the conventional machine, the web it) which would have been coated on both sides with the asphaltic material, would then pass around the roll 21 and sticking would be prevented by the presence of granules between the asphaltic coating and the roll 21 and anti-stick material would be applied by the mechanism 22, as is well known in the art, before the material passed in a reverse direction about the roll 23.

According to the present invention, instead of going from the granule applying station G directly to the roll 21, the web is caused to pass in the other direction, i.e. with the granules outwardly around a roll 24. The web will not stick to the roll 24 because it has not been coated on the underside with asphalticmaterial and the flexing of the web 10 around the roll 24 causes the excess granules or so-called hitch-hikers to be freed or loosened from mechanical bond and to fall into collecting troughs 25' and 26. The spill granules from the headlap sections are deflected into the trough 25 by the battles 25a and the spill granules from the exposed portions e are deflected into the trough 26 by the bafiles 26a. From the troughs 25 and as, the spill granules are carried by conveyors, such as diagrammatically indicated at 27, to-the side of the machine whereby bucket conveyors the granules are remaining on the web can be held down to between twenty-one and twenty-four pounds per one hundred square feet in the case of #11 granules. With the weight of granules kept down in this way, each individual granule is firmly bonded in the asphalt layer and not held mechanically, so that the smoothness of the granule surface is greatly improved, and a better looking product results. An additional feature of the invention is the clean line of demarcation which may be achieved between the bands of different colored granules. This makes it possible to carry the headlap portion farther down, using the inert-- with something else. By the practice of the present invention that weight may be replaced with inexpensive material, ie the asphalt and filler or stabilizer. It is a fact that if the quantity of asphalt is increased a larger percentage of stabilizer can be used and the material used as a stabilizer is extremely cheap, running considerably less than the asphalt. By the practice of the present invention, therefore, the manufacturing cost of the roofing material is substantially reduced not only because of the in production elficiencyand the resulting material has an improved appearance.

It will be understood that the specific pattern illustrated in FIGURES 2 and 3 is not a limitation upon the inven tion. The procedure of applying patterned granules is conventional and sometimes only one or two colors are applied and sometimes more than four colors are applied. Sometimes no headlap granules are applied, as tor example on rolls, and on shingles to be laid in a diamond pattern, and the like. Regardless of how many colors are applied, the passing of the web around the roll 24 prevents the build up ofexcessive thickness of granules on the web and it is from this that the various advantages herein recited fiow.

Various modifications may be made without departing from the spirit of the invention and there is no intent to limit the claim otherwise than as specifically set forth herein. 1

What is claimed is: g

In the manufacture of roofing material of the type comprising a web of base material coated on both sides with an asphaltic material and having'roofing granules embedded in said asphaltic coating on one surface of said material; the steps of first causing said web to be coated with an asphaltic material on one side only, applying granules to said coated side, then immediately after the application of said granules passing said web around a roll with the granule face outward whereby to free granules in excess of substantially a single layer, immediately thereafter coating the other side of said web with an asphaltic material, and then applying to said other side an anti-stick material so that said web may pass around a roll with its last coated side against a roll without sticking thereto.

References Cited in the file of this patent UNITED STATES PATENTS 1,289,328 Wardell Dec. 31,- 1918 1,618,192 I Heppes -Feb.22, 1927 1,807,918 Kerschbraun et al. June 2, 1931 1,854,071 Schacht Apr. 12, 1932 1,856,744 Carlton May 3, 1932 2,056,275 'Holdsworth Oct. 6, 1936 2,302,183 Burns Nov. 17, 1942 2,548,029 Kurtz et al; Apr. 10, 1951 2,721,144 Penley Oct. 18,1955 

